From 39ad3b9d9e16b880ae175af2f3bf02af4c3b6e28 Mon Sep 17 00:00:00 2001 From: Kyle McMartin Date: Dec 10 2010 15:51:13 +0000 Subject: PCI: Disable ASPM if BIOS asks us to --- diff --git a/kernel.spec b/kernel.spec index 9286d80..054236d 100644 --- a/kernel.spec +++ b/kernel.spec @@ -612,6 +612,7 @@ Patch204: linux-2.6-debug-always-inline-kzalloc.patch Patch380: linux-2.6-defaults-pci_no_msi.patch Patch381: linux-2.6-defaults-pci_use_crs.patch Patch383: linux-2.6-defaults-aspm.patch +Patch384: pci-disable-aspm-if-bios-asks-us-to.patch Patch385: ima-allow-it-to-be-completely-disabled-and-default-off.patch @@ -1194,6 +1195,7 @@ ApplyPatch linux-2.6-defaults-pci_no_msi.patch ApplyPatch linux-2.6-defaults-pci_use_crs.patch # enable ASPM by default on hardware we expect to work ApplyPatch linux-2.6-defaults-aspm.patch +ApplyPatch pci-disable-aspm-if-bios-asks-us-to.patch #ApplyPatch ima-allow-it-to-be-completely-disabled-and-default-off.patch @@ -1926,6 +1928,10 @@ fi # || || %changelog +* Fri Dec 10 2010 Kyle McMartin +- pci-disable-aspm-if-bios-asks-us-to.patch: Patch from mjg59 to disable + ASPM if the BIOS has disabled it, but enabled it already on some devices. + * Thu Dec 09 2010 Kyle McMartin - Snarf patch from wireless-next to fix mdomsch's orinico wifi. (orinoco: initialise priv->hw before assigning the interrupt) diff --git a/pci-disable-aspm-if-bios-asks-us-to.patch b/pci-disable-aspm-if-bios-asks-us-to.patch new file mode 100644 index 0000000..f9f2935 --- /dev/null +++ b/pci-disable-aspm-if-bios-asks-us-to.patch @@ -0,0 +1,144 @@ +From linux-kernel-owner@vger.kernel.org Mon Dec 6 14:01:17 2010 +From: Matthew Garrett +To: linux-pci@vger.kernel.org +Cc: linux-kernel@vger.kernel.org, jbarnes@virtuousgeek.org, + Matthew Garrett +Subject: [PATCH v2] PCI: Disable ASPM if BIOS asks us to +Date: Mon, 6 Dec 2010 14:00:56 -0500 +Message-Id: <1291662056-6055-1-git-send-email-mjg@redhat.com> + +We currently refuse to touch the ASPM registers if the BIOS tells us that +ASPM isn't supported. This can cause problems if the BIOS has (for any +reason) enabled ASPM on some devices anyway. Change the code such that we +explicitly clear ASPM if the FADT indicates that ASPM isn't supported, +and make sure we tidy up appropriately on device removal in order to deal +with the hotplug case. If ASPM is disabled because the BIOS doesn't hand +over control then we won't touch the registers. + +Signed-off-by: Matthew Garrett +--- + +Implement Rafael's suggestion to use two separate functions, and also +ensure that we clear the clkpm bit as well as the ASPM bits. + + drivers/pci/pci-acpi.c | 1 + + drivers/pci/pcie/aspm.c | 21 +++++++++++++++++---- + include/linux/pci-aspm.h | 5 ++++- + 3 files changed, 22 insertions(+), 5 deletions(-) + +diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c +index 24e19c5..d7ea699 100644 +--- a/drivers/pci/pci-acpi.c ++++ b/drivers/pci/pci-acpi.c +@@ -399,6 +399,7 @@ static int __init acpi_pci_init(void) + + if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) { + printk(KERN_INFO"ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n"); ++ pcie_clear_aspm(); + pcie_no_aspm(); + } + +diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c +index 7122281..8112415 100644 +--- a/drivers/pci/pcie/aspm.c ++++ b/drivers/pci/pcie/aspm.c +@@ -68,7 +68,7 @@ struct pcie_link_state { + struct aspm_latency acceptable[8]; + }; + +-static int aspm_disabled, aspm_force; ++static int aspm_disabled, aspm_force, aspm_clear_state; + static DEFINE_MUTEX(aspm_lock); + static LIST_HEAD(link_list); + +@@ -139,7 +139,7 @@ static void pcie_set_clkpm(struct pcie_link_state *link, int enable) + { + /* Don't enable Clock PM if the link is not Clock PM capable */ + if (!link->clkpm_capable && enable) +- return; ++ enable = 0; + /* Need nothing if the specified equals to current state */ + if (link->clkpm_enabled == enable) + return; +@@ -498,6 +498,10 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev) + struct pci_dev *child; + int pos; + u32 reg32; ++ ++ if (aspm_clear_state) ++ return -EINVAL; ++ + /* + * Some functions in a slot might not all be PCIe functions, + * very strange. Disable ASPM for the whole slot +@@ -563,12 +567,15 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev) + struct pcie_link_state *link; + int blacklist = !!pcie_aspm_sanity_check(pdev); + +- if (aspm_disabled || !pci_is_pcie(pdev) || pdev->link_state) ++ if (!pci_is_pcie(pdev) || pdev->link_state) + return; + if (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && + pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) + return; + ++ if (aspm_disabled && !aspm_clear_state) ++ return; ++ + /* VIA has a strange chipset, root port is under a bridge */ + if (pdev->pcie_type == PCI_EXP_TYPE_ROOT_PORT && + pdev->bus->self) +@@ -641,7 +648,7 @@ void pcie_aspm_exit_link_state(struct pci_dev *pdev) + struct pci_dev *parent = pdev->bus->self; + struct pcie_link_state *link, *root, *parent_link; + +- if (aspm_disabled || !pci_is_pcie(pdev) || ++ if ((aspm_disabled && !aspm_clear_state) || !pci_is_pcie(pdev) || + !parent || !parent->link_state) + return; + if ((parent->pcie_type != PCI_EXP_TYPE_ROOT_PORT) && +@@ -899,6 +906,12 @@ static int __init pcie_aspm_disable(char *str) + + __setup("pcie_aspm=", pcie_aspm_disable); + ++void pci_clear_aspm(void) ++{ ++ if (!aspm_force) ++ aspm_clear_state = 1; ++} ++ + void pcie_no_aspm(void) + { + if (!aspm_force) +diff --git a/include/linux/pci-aspm.h b/include/linux/pci-aspm.h +index 91ba0b3..ce68105 100644 +--- a/include/linux/pci-aspm.h ++++ b/include/linux/pci-aspm.h +@@ -27,6 +27,7 @@ extern void pcie_aspm_init_link_state(struct pci_dev *pdev); + extern void pcie_aspm_exit_link_state(struct pci_dev *pdev); + extern void pcie_aspm_pm_state_change(struct pci_dev *pdev); + extern void pci_disable_link_state(struct pci_dev *pdev, int state); ++extern void pcie_clear_aspm(void); + extern void pcie_no_aspm(void); + #else + static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) +@@ -41,7 +42,9 @@ static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) + static inline void pci_disable_link_state(struct pci_dev *pdev, int state) + { + } +- ++static inline void pcie_clear_aspm(void) ++{ ++} + static inline void pcie_no_aspm(void) + { + } +-- +1.7.3.2 + +-- +To unsubscribe from this list: send the line "unsubscribe linux-kernel" in +the body of a message to majordomo@vger.kernel.org +More majordomo info at http://vger.kernel.org/majordomo-info.html +Please read the FAQ at http://www.tux.org/lkml/ +